ultralytics 8.0.120 CLI support for SAM, RTDETR (#3273)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

ultralytics/nn/tasks.py

@@ -243,6 +243,8 @@ class DetectionModel(BaseModel):
             m.stride = torch.tensor([s / x.shape[-2] for x in forward(torch.zeros(1, ch, s, s))])  # forward
             self.stride = m.stride
             m.bias_init()  # only run once
+        else:
+            self.stride = torch.Tensor([32])  # default stride for i.e. RTDETR
 
         # Init weights, biases
         initialize_weights(self)